In the background art of this technical field, in order to evenly distribute gas-liquid two-phase flow on an inlet side of a heat exchanger that functions as an evaporator and to exhibit the maximum performance of a heat exchanger, Patent Literature 1 discloses that, a chamber portion is connected to upstream piping of a distributor so as to be orthogonal thereto, the chamber portion having a diameter larger than that of the upstream piping, and thereby uneven refrigerant distribution improves.
In addition, a heat exchanger disclosed in Patent Literature 2 is a fin and tube type heat exchanger configured to include a heat-transfer pipe having a part configured of four or more paths, in order to reduce degradation of heat exchanger performance of the heat exchanger even in a case where a refrigerant having a significant temperature change during heat release is used, in which paths are configured to have substantially parallel flow of the refrigerant in a stage direction, and, further, refrigerant inlets of the paths are configured to be positioned to be substantially adjacent in a case of being used as a radiator. In this manner, the description is read that it is possible to reduce the degradation of heat exchanging performance, without an increase in draft resistance of an air-side circuit and an increase in manufacturing cost (refer to Abstract).
In addition, Patent Literature 3 is disclosed. In order to provide an air conditioner in which a melted residue of frost is removed and it is possible to realize high-performance heating capacity at a low cost, an air conditioner disclosed in Patent Literature 3 is an air conditioner that includes a refrigeration cycle in which at least a compressor, an indoor heat exchanger, an expansion valve, and an outdoor heat exchanger are connected via a refrigerant circuit, in which the outdoor heat exchanger is configured of a plurality of systems of refrigerant flow paths, any inlets of the plurality of systems of refrigerant flow paths are positioned in a refrigerant flow pipe on the uppermost stage or the second stage from the uppermost stage of the outdoor heat exchanger when the outdoor heat exchanger is used as an evaporator. In this manner, the description is read that it is possible to realize such an air conditioner (refer to Abstract).